In wireless mobile communication systems, antenna diversity is one of the most important techniques to improve the performance. Codes suitable for antenna diversity which achieve full diversity, full rate and good coding gains are preferred when there is a small number of parallel channels. A concatenated space-time block code and multiple trellis coded modulation (STBC-MTCM) scheme achieves th...

This paper studies the ensemble selection problem for unsupervised learning. Given a large library of different clustering solutions, our goal is to select a subset of solutions to form a smaller but better performing cluster ensemble than using all available solutions. We design our ensemble selection methods based on quality and diversity, the two factors that have been shown to influence clu...

This paper presents a Space Time Block Code structure using spread spectrum in multi user context employing code division multiple access (CDMA). This communication system can guarantee full rate full diversity because its based on the famous Alamouti code using two transmit antennas and two receive antennas. The originality of this paper consists on extending the use of ST block codes to a mul...

It is known that by employing space-time-frequency codes (STFCs) to frequency selective MIMO-OFDM systems, all the three diversity viz spatial, temporal and multipath can be exploited. There exists space-time-frequency block codes (STFBCs) designed using orthogonal designs with constellation precoder to get full diversity (Z.Liu, Y.Xin and G.Giannakis IEEE Trans. Signal Processing, Oct. 2002). ...

A major challenge in gene library generation is to guarantee a large functional size and diversity that significantly increases the chances of selecting different functional protein variants. The use of trinucleotides mixtures for controlled randomization results in superior library diversity and offers the ability to specify the type and distribution of the amino acids at each position. Here w...

Performance evaluation of super orthogonal space-time trellis codes for non-frequency selective fading channels & frequency selective fading channels. The analysis is done in presence of fast fading, block fading and quasi-static fading in Rayleigh, and Nakhagami fast fading channels along with comparison. While providing full diversity and full rate, the structure of our new codes allows an in...

A universal framework is developed for constructing full-rate and full-diversity coherent space–time codes for systems with arbitrary numbers of transmit and receive antennas. The proposed framework combines space–time layering concepts with algebraic component codes optimized for single-input–single-output (SISO) channels. Each component code is assigned to a “thread” in the space–time matrix,...

Multiple-Input-Multiple-Output (MIMO) systems are under intense investigation for wireless transmission systems. Space-Time Coding is an efficient approach to exploit the huge diversity offered by the MIMO channel. One of the main problems of Space-Time Block Coding (STBC) is that the offered diversity can only be exploited by the optimal ML receiver which has exponential complexity. In contras...

Orthogonal transmitter diversity such as frequency diversity and time diversity is quite simple to implement and, with optimum signal combining, can take full advantage of fading multipath channels. However, such a scheme has a bandwidth efficiency that decreases inversely with the number of diversity branches making it less attractive in wireless communications applications. This paper conside...

This paper proposes a full-rate, full-diversity spacetime block code (STBC) with low maximum likelihood (ML) decoding complexity and high coding gain for the 4 transmit antenna, 2 receive antenna (4×2) multiple-input multiple-output (MIMO) system that employs 4/16-QAM. For such a system, the best code known is the DjABBA code and recently, Biglieri, Hong and Viterbo have proposed another STBC (...